Standardization works of international mobile telecommunication (IMT)-advanced which is a next generation (i.e., post 3rd generation) mobile communication system are carried out in the international telecommunication union radio communication sector (ITU-R). The IMT-advanced aims to support an Internet protocol (IP)-based multimedia service with a data transfer rate of 1 Gbps in a stationary or slowly moving state or 100 Mbps in a fast moving state.
3rd generation partnership project (3GPP) is a system standard satisfying requirements of the IMT-advanced, and prepares LTE-advanced which is an improved version of long term evolution (LTE) based on orthogonal frequency division multiple access (OFDMA)/single carrier-frequency division multiple access (SC-FDMA) transmission. The LTE-advanced is one of promising candidates for the IMT-advanced. A relay station technology is one of main technologies for the LTE-advanced.
A relay station is a device for relaying a signal between a base station and a user equipment, and is used for cell coverage extension and throughput enhancement of a wireless communication system.
A transmission format such as a transmission mode of a downlink channel is used for communication between the relay station and the base station. A communication connection cannot be maintained when information regarding the transmission format is not correctly delivered to the relay station, the base station, the user equipment, or the like. Therefore, there is a need for a communication method for correctly delivering the transmission format by considering an operation characteristic of the relay station, the base station, and the user equipment.